This was a project for a freelance client. My client was looking for a way to build a custom form that would generate a PDF that was pre-filled with the data entered in the form.
This was challenging as my client had a limited budget and did not want to license paid software to get the job done.
I ended up using a free plugin and then used the shortcodes to generate a custom PDF output.
At one point I had also looked at setting up a custom PHP page within the wordpress site and use a PDF library, but that was not needed. The free plugin I ended up using was Fluent Forms.